Derivative Instruments and Other Financial Instruments Used For Hedging (Details 3) - Fair value hedges - Interest rate derivative contracts - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Amount and location of net gains and losses
Derivative	$ (2)	$ 7
Hedged Item	1	(7)
Hedge Ineffectiveness	(1)	0
Designated as Hedging Instrument
Amount and location of net gains and losses
Derivative	(2)	7
Hedged Item	1	(7)
Hedge Ineffectiveness	$ (1)	$ 0

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

+ References

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- Definition

Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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